Answer:

Step-by-step explanation:
4 x 10^7 is 40000000
4 x 10^3 is 4000
We are told that 4x10^7 is something times as much as 4x10^3
So we will work backwards to find the answer,
If you divide 40000000 by 4000 you will get 10000
10000 is the same as 10^4
Answer:
83.33%
Step-by-step explanation:
300 - 50 = 250
250/300 = 0.8333 or 83.33%
Answer: 1045 cm of red ribbon and 1045 cm of yellow ribbon
<u>Step-by-step explanation:</u>
Let R represent the amount red ribbon and Y represent the amouont of yellow ribbon.
- bought the same lengths of red and yellow: R = Y
- after used 286 of red, yellow is 5 times the remaining red; 5(R - 836) = Y
Use substitution method to solve:
5(R - 836) = R
5R - 4180 = R <em>distributed 5 on the left side</em>
4R - 4180 = 0 <em>subtracted R from both sides</em>
4R = 4180 <em>added 4180 to both sides</em>
R = 1045 <em>divided both sides by 4</em>
Answer:
z = 8
Step-by-step explanation:
3/4 (z+4)=9
3/4z + 3 = 9
3/4z = 6
z = 8
Answer:
Below.
Step-by-step explanation:
To find the number of students in each grade you multiply the marks by the frequency density. The number of students is given by the area under the rectangles.
So to find the number of students with grade U (< 160) it is:
120 * 0.2 + 40*0.5
= 24 + 20
= 44.
The number for Grade E
= (200 - 160) * 0.5
= 40 * 0.5
= 20.
The others can be found in the same way.